DE 199 01 295 A1 discloses an optical imaging device in which the outer mount and an inner ring that can be adjusted relative to this outer mount are preferably integrally formed in one piece, i.e., as a monolithic unit. Between the inner ring and the outer mount, a manipulator device for the path-controlled displacement of the optical element, which is mounted in the inner ring in a direction perpendicular to the optical axis consists of a system of peripheral slots with connecting elements located between, a swivel joint and at least one adjustable joint with an adjusting element.
The drawback of this solution is that, in particular, because of the plurality of differently shaped configurations, these manipulator units, which in the document cited are called manipulator elements, have a complicated and unsymmetrical structure that is unsuitable for symmetrical systems, or can give rise to system instabilities. Specifically, the connecting elements, which have a stiffening effect in the direction of the optical axis but which are kinematically superfluous, increase the production costs and, depending on their number, require additional displacement forces and have the effect that deformations have a greater impact on the inner part. In addition, the swivel joints require an additional leaf-type spring and, in order to ensure the intended adjustment, must be moved in two directions that are oppositely oriented to each other, which requires pretensioning elements for both directions.
WO 2005/101131 A1 describes a lens mount, therein called a receiving assembly for positioning an optical element, comprising a first frame and three identical manipulator units, called holding units, which are equiangularly distributed along the circumference of the first frame and hold a second frame which supports a lens. The holding units are additional components, which, inter alia, lead to increased production and assembly costs. Thus, this is not a monolithic lens mount.
DE 100 51 706 A1 also discloses a mount which is divided by means of several cuts in the material into an inner mount and an outer mount, which remain connected to each other between the cuts in the material, said joints, in terms of the invention, being manipulator units. The cuts in the material are configured such that, when the connections are actuated by manipulators that act upon the connections, the inner mount, and consequently the mounted lens, can be axially moved, which mount, unlike the mount of the present invention, is therefore not a radially displaceable mount.
A lens mount that is integrally formed in one piece and thus is monolithic is also known from EP 1 577 693 A2. In a preferred embodiment, an inner ring is connected to an outer mount by way of three manipulator units, which in the document cited are called adjustable joints, each having two hinged brackets and an adjusting element between. To allow a lateral adjustment of the inner ring and thus of the optical element, actuators act on the swivel joints.
In contrast to DE 199 01 295 A1 mentioned above, the solution presented in this document is marked by a higher temperature stability.
As EP 1 577 693 A2 explains, when the optical element, e.g., a lens, is heated, the problem arises that it is very difficult for the heat to dissipate by way of the connections between the inner ring and the outer mount, of which there are only few, and those that exist are narrow. The resulting temperature differences have a negative effect on the imaging quality since, due to changes in the temperature, especially a change in length of the hinged brackets that extend in the same direction leads to a displacement of the inner ring in this same direction, which in turn leads to aberrations and comatic defects.
The lens mount according to EP 1 577 693 A2 avoids this problem mainly in that, in the tangential direction, the hinged brackets which are offset by 120° relative to each other act upon the outer peripheral area of the inner ring and on the inner peripheral area of the outer mount counterclockwise away from the inner ring. In this case, a change in the length of the hinged brackets is translated into a uniform direction of rotation. Rotations of this type do not lead to aberrations, especially not with a lens as an optical element.
A lens mount according to EP 1 577 693 A2 is also said to have the advantage that by shortening the hinged brackets, it is possible to increase the lateral stiffness of the inner ring connection, which has the effect that the lens mount with the lens mounted in it has a greater stiffness against vibrations inherent in the system. However, a higher lateral stiffness due to shortened hinged brackets is obtained at the expense of the sensitivity of the adjustment, which is determined not only by the length but also by the deflection of the hinged brackets.
The length of the hinged brackets, however, continues to be determined by the admissible material load. This means that if, at a preset adjustable movement and a preset sensitivity, the admissible material load is reached, the hinged brackets cannot be further shortened in order to increase the stiffness and inherent vibrations [sic]. Consequently, two relatively thin and, relative to the cross section, relatively long hinged brackets will always be required to ensure functionability as an adjusting unit or joint, which invariably limits the lateral and axial stiffness that can be reached.
DE 10 2007 030 579 A1 describes a first embodiment of a laterally adjustable lens mount which is essentially equivalent to a lens mount disclosed in EP 1 577 693 A2, which means that three manipulator units that are offset by 120° relative to one another are combined into a single element which, along its fixed end, transitions into two tangentially oriented hinged brackets, which in this document are called joining strips, which joining strips are connected to the inner mount section and the outer mount section.
In a second embodiment, the joining strips that connect the element to the inner and outer mount sections are radially oriented, which ensures a higher lateral stiffness.
However, when the lever is deflected by introducing, by way of a manipulator, a radially acting force into the free lever end, the resulting tensile loads in the radial joining strips are far greater than those in the tangential joining strips. Thus, the generation of undesirable tensions in the inner ring is unavoidable.
In both embodiments, the manipulator units are simple lever mechanisms, the transmission of which is determined by the length of the element and the deflection of the joining strips in the radial direction. To obtain a high sensitivity at the associated adjustable movements, the joining strips and/or hinged brackets are designed to be long, which can cause them to be subjected to torsional forces in the axial direction.